SQL error “ORA-01722: invalid number”

Question

A very easy one for someone, The following insert is giving me the

ORA-01722: invalid number

why?

INSERT INTO C         


        

Answer 1

try this as well, when you have a invalid number error

In this a.emplid is number and b.emplid is an varchar2 so if you got to convert one of the sides

where to_char(a.emplid)=b.emplid